1. Field of the Invention
The present invention relates to a splice tube for joining cables under tension and, more particularly, to a splice tube used in a cable truss system.
2. Description of Related Art
Roof trusses or roof support systems for mines provide support for the immediate roof strata. One type of roof support system utilizes a flexible cable extending between rigid rock anchors or bolts. The cable truss includes two boreholes spaced from each other with a cable bolt secured within each of the boreholes. A leading end of each cable bolt is secured within the borehole with a trailing end extending from the borehole. A splice tube couples the trailing end of each cable. The splice tube generally includes two passageways extending through the tube, although certain truss systems utilize rectangular tubing with one passageway. Each trailing end of the cables is pulled through the passageways in opposite directions and the cable bolts are then tensioned. Wedges are positioned in the passageways next to the cables. As the cables are released and drawn backwards, the wedges are moved further into the passageways and grip the cables thereby securing the cables relative to the splice tube. In certain designs, the passageways are curved to reduce sharp edges and prevent loads from being concentrated in a particular area.
With the cable truss system described above, the wedges are typically positioned next to the cables in the passageway by a worker. The wedges may be misplaced or dropped during the installation, which may require additional time to locate the wedges or additional cost in procuring extra wedges.
U.S. Pat. No. 7,384,216 discloses a cable coupler with a wedge assembly having a clip attached to the body of the coupler adjacent the passageways extending through the body. The clip is shiftable between a closed position in which the clip is positioned to prevent an adjacent wedge assembly from exiting the corresponding passageway and an open position in which the adjacent wedge assembly is insertable into the corresponding passageway. Further, a plug may be disposed within the wedge assembly to maintain the wedges slightly apart from each other and assist in holding the wedge assembly in a position to receive the cable.